Along with worldwide applications of electrical appliances, extension cords become essential components in the electrical appliances, such as sockets and plugs. Conventional sockets and plugs are generally independent components with single function. People must resort to multi-functional socket to satisfy requirements of users when plurals of electrical device need socket at the same time. Furthermore, because conventional socket has its jacks exposed outside and without shield, there is a fear to get an electric shock or have water entry into the socket.
Hence, it is desired to provide safe and multi-sectional extension cords to satisfy user's various requirements.